It doesn't do miracles. Just like The Foundry's 3D Tracker, it only does uncalibrated tracks, meaning it bears no relation to any real geometry or realworld units. None of this 3D stuff does and it's still gonna be tricky doing anything with it that requires to do more than matching some of AE's own stuff with an existing shot. If you need it to work for 3D programs and think you are getting away fro free when upgrading to CS6, then that's probably an illusion. You still need SynthEyes, PFTrack, Matchmover for that, you may just need them a little less often for more trivial things.

If you want to get 3-D camera data and real world geometry from camera tracking, try Blender. It does an amazingly good job for an open source software. The latest version will also export to AE.

The built in camera tracker with CS 6 does an amazing job on certain kinds of shots. Blenders built in tracking does an amazing job on similar kinds of shots. Neither work with all shots, nor will any 3-D tracking software work with every shot. If your production is going to utilize any kind of 3-D tracking them, you had better do some production planning. There is nothing worse than trying to fix something that can't be fixed when just a little bit of planning and a little better camerawork would make the job easy.

Regarding the 3D Camera Tracker compared with the camera tracker from The Foundry:

Our goal was to make a camera tracker that was very, very easy to use that would give good results in the great majority of cases. We deliberately simplified in a few areas where added complexity would make things harder but might also add some extra configurability to work with difficult scenes. For this reason, we think that most people will be satisfied with our 3D Camera Tracker most of the time... but you may need to use something else for especially tricky scenes.

Will the version of Mocha AE that ships with CS6 have the camera solver for 3d? Looking at this article, it leads me to believe that the version that ships with AE will not have the solver included.

"mocha AE is available in two version: mocha AE CS6, which comes as a free bundle with every copy of the newly launched Adobe After Effects CS6 and is specifically optimized for After Effects; and the mocha AE v3 standalone application, which adds new Camera Solve features"

I was excited to see the 3d camera solver in mocha, but hoping that it would come with the version included.